The present invention provides a process for mixing or dispersing liquids. In particular, a process for the production of a finely divided liquid dispersion is provided, as well as mixing devices for carrying out the process.
European Patent Publication EP 0776 997 A1 describes a method for the production of a finely divided dispersion of solids in which a pre-dispersion is pumped through one or more slotted nozzles. The particle size of the dispersed phase lies in the region of 0.01 xcexcm to 20 xcexcm. The diameter of the nozzle bore is 0.05 mm to 1 mm. The ratio of bore length to bore diameter is 1:1 to 1:10. A preferred combination includes a device which has two nozzle bodies with the nozzles lying opposite their outlet. Also described are devices in which the crude dispersion or pre-dispersion is pumped through two or more nozzles having an equal or decreasing bore diameter. The slotted nozzle suitably consists of a ceramic material, for example, zirconium oxide, or a metal coated with ceramic.
International Patent Publication WO 97/17946 describes a method for the production of a liposome dispersion in which an aqueous pre-dispersion of one or more amphiphilic substances is pumped at 600 bar to 900 bar through at least one homogenizing nozzle having a diameter of 0.1 mm to 0.5 mm. The homogenizing nozzle has an inlet channel and an outlet channel and includes a hard ceramic plate, in which the bore is situated, pressed in a steel body. The inlet channel and the outlet channel are also incorporated in the steel body. When several nozzles are used, they are arranged opposite to each other and have a parallel inflow. The pre-dispersion is pumped in the circuit through the homogenizing nozzle until the average particle size of the liposome dispersion is between about 35 nm and about 80 nm.
The devices described above suffer from the drawback that intermixing is often inefficient or incomplete. Moreover, such devices require high amounts of energy to achive viable levels of intermixing.
Accordingly, it would be desirable to provide a method for mixing or dispersing liquids which permits an improved intermixing with lower energy expenditure compared with the state of the art.
One embodiment of the invention is a process for mixing or dispersing liquids that includes introducing liquids to be mixed or dispersed into a mixing device having a cylindrical support. The cylindrical support includes an inlet nozzle having a bore which is in fluid communication through a turbulence chamber with a bore of an outlet nozzle, wherein the bores of the nozzles are axially spaced apart relative to one another. The liquids then enter the turbulence chamber through the bore of the inlet nozzle where the liquids are subjected to turbulence, i.e., are mixed or dispersed. The mixed or dispersed product is thereafter recovered from the outlet nozzle.
Another embodiment of the present invention is a mixing device having a cylindrical support. The cylindrical support includes an inlet nozzle having a bore which is in fluid communication through a turbulence chamber with a bore of an outlet nozzle, wherein the bores of the nozzles are axially spaced apart relative to one another.
Another embodiment of the invention is a scale up arrangement wherein a plurality of nozzles are disposed within the cylindrical support.
A further embodiment of the invention is a scale up arrangement that includes a first support disk, a turbulence chamber, and a second support disk, which are positioned in sequence in a conduit. The first support disk consists of a plurality of inlet nozzles having a bore diameter of about 0.05 mm to about 1 mm. The second support disk contains a plurality of outlet nozzles having a bore diameter of about 0.05 mm to about 1 mm. The bores of the inlet nozzles are in fluid communication with the bores of the outlet nozzles through the turbulence chamber and the bores of the inlet nozzles and outlet nozzles are axially spaced apart relative to one another.